The present invention relates to methyl, substituted propyl-substituted pentamethyl indane derivatives defined according to the structure: ##STR4## wherein R.sub.1 represents hydroxyl or methyl; R.sub.2 represents hydrogen, chloro or OR.sub.6 and R.sub.3 represents hydrogen or methyl with the provisos that:
(i) when R.sub.1 is hydroxyl, R.sub.2 is hydrogen and R.sub.3 is methyl; and PA1 (ii) when R.sub.1 is methyl, one of R.sub.2 is chloro or OR.sub.6 and R.sub.3 is hydrogen PA1 U.S. Pat. No. 4,295,978 issued on Oct. 20, 1981; and PA1 U.S. Pat. No. 4,650,603 issued on Mar. 17, 1987. PA1 U.S. Pat. No. 3,532,719; PA1 U.S. Pat. No. 3,978,090.
wherein R.sub.6 is methyl, ethyl, n-propyl or i-propyl and wherein the structure represents a mixture wherein in the mixture in one of the compounds R.sub.4 and R.sub.4 ' are both methyl; and in the other compounds one of R.sub.4 or R.sub.4 ' is methyl and the other is ethyl and organoleptic uses thereof in augmenting, enhancing or imparting aroma nuances in or to perfume compositions, perfumed articles and colognes.
There has been considerable work performed relating to substances which can be used to impart (to alter, modify or enhance) fragrances to (or in) various consumable materials. These substances are used to diminish the use of natural materials some of which may be in short supply and to provide more uniform properties in the finished product. Musky aromas are highly desirable in several types of perfume compositions and for use in perfumed articles. Natural "musky" aromas are highly sought after and heretofore have been virtually impossible to duplicate. Accordingly, a need exists in the perfume art to duplicate as closely as possible natural musky aroma nuances.
Oxygenated indane derivatives such as those having the structure: ##STR5## and having the structure: ##STR6## are known in the prior art to give rise to musk aromas. Thus, U.S. Pat. Nos. 3,660,311 of May 2, 1972 and 4,162,256 of Jul. 24, 1979 disclose the perfumery use of the compound having the structure: ##STR7## Furthermore, the compound having the structure: ##STR8## is disclosed as having musk aromas in the following U.S. patents: U.S. Pat. No. 3,360,530 issued on Dec. 26, 1967;
Furthermore, processes for the production of such materials are set forth in:
U.S. Pat. No. 3,910,964;
as well as:
Nothing in the prior art however discloses the unobvious, unexpected and advantageous properties of the methyl, substituted propyl-substituted pentamethyl indane derivatives of our invention; and nothing in the prior art discloses the unexpected, advantageous techniques of preparing the methyl, substituted propyl-substituted pentamethyl indane derivatives of our invention via the newly discovered rearrangement reaction set forth in detail and exemplified, infra.